The present invention relates to a method of producing copies of at least part of a nucleic acid strand.
In the field of genetic engineering, it is often the case that only a very small amount of a nucleic acid is present in a sample but that a somewhat larger amount of the full or part of the sequence is required for the purposes of research or a diagnostic test. Alternatively, it may be necessary to know whether or not a particular nucleic acid is present at all in a sample (e.g. to determine whether a person has been infected by a particular virus, either DNA or RNA, or has a particular sequence, present or absent, in their nucleic acid). Since the amount of the nucleic acid, if present in the sample, would be below detectable limits, it is necessary to subject the sample to an amplification reaction such that an enhanced amount of the nucleic acid (if present) is produced. A test may then be conducted to determine the presence or otherwise of the nucleic acid. If the test is positive then this confirms that the nucleic acid was present in the original sample. Conversely if the test is negative then this is confirmation that the nucleic acid was not present in the original sample.